.left-nav{
  width: 85%;
  margin: 0 auto;
}
::-webkit-scrollbar {
  width: 8px;
  height: 100%;
  border-radius: 5px;
  background: #e1e5ea;
}
::-webkit-scrollbar-thumb {
  background: #4c97da;
  margin: 0 auto;
  box-sizing: border-box;
  border-radius: 5px;
}
@media screen and (max-width:721px){
  .left-nav{
    width: 100%;
    margin: 0 auto;
  }
}
